Simplify worker.work() by moving some functionalities to relevant methods.
Job status should be updated during job.perform().
Pull argument parser defaults from environment variables.
Merge pull request #321 from selwin/cleanup-worker.work

Simplify worker.work() by moving some functionalities to relevant methods
Use get_state() instead of .state in rqinfo
Merge pull request #329 from olingerc/workonrqinfo

Use get_state() instead of .state in rqinfo
Don't expose the envvar values through `rqinfo -h`.
Merge branch 'malthe-default-to-environment-args'